1.2 Electron Orbitals and Configurations

Question 1

principle quantum number

Answer 1

• symbol: n
• defines: size and energy of the shell
• n = 1, 2, 3, 4

Question 2

• symbol: n
• defines: size and energy of the shell
• n = 1, 2, 3, 4

Answer 2

principle quantum number

Question 3

angular quantum number

Answer 3

• symbol: l
• defines: shape of sub shell
• n = 0 to n-1l = 0 = s orbitall = 1 = p orbitall = 2 = d orbitall = 3 = f orbital

Question 4

• symbol: l
• defines: shape of sub shell
• n = 0 to n-1

Answer 4

angular momentum quantum number

Question 5

magnetic quantum number

Answer 5

• symbol: ml
• defines: direction
• n = -l .. 0 .. +l
• ml will tell you how many electron pairs are in the orbital
  0 = 1 pair
  -1, 0, +1 = 3 pairs

Question 6

• symbol: ml
• defines: direction
• n = -l .. 0 .. +l

Answer 6

magnetic quantum number

Question 7

spin magnetic quantum number

Answer 7

• symbol: ms
• defines: spin
• n = -1/2 or +1/2

Question 8

• symbol: ms
• defines: spin
• n = -1/2 or +1/2

Answer 8

spin magnetic quantum number

Question 9

draw all the shapes of orbitals in order of s, p, d, f

Answer 9

Question 10

aufbau rule

Answer 10

Electrons occupy orbitals in order of increasing energy, eg the lowest energy orbital is filled first

Question 11

Electrons occupy orbitals in order of increasing energy, eg the lowest energy orbital is filled first

Answer 11

aufbau rule

Question 12

hunds rule

Answer 12

degenerate (equal energy) orbitals are occupied singularly before pairing

Question 13

degenerate (equal energy) orbitals are occupied singularly before pairing

Answer 13

hunds rule

Question 14

degenerate

Answer 14

of equal energy

Question 15

of equal energy

Answer 15

degenerate

Question 16

No 2 electrons can have the same 4 quantum numbers numbers and if there are 2 electrons, their spin must be opposite

Answer 16

pauli exclusion principle

Question 17

pauli exclusion principle

Answer 17

No 2 electrons can have the same 4 quantum numbers numbers and if there are 2 electrons, their spin must be opposite

Question 18

atomic orbital

Answer 18

a region of high probability of finding an electron

Question 19

a region of high probability of finding an electron

Answer 19

atomic orbital

Question 20

how many electrons does an orbital hold

Answer 20

maximum of two

Question 21

how many electrons do s, p, and d orbitals hold each

Answer 21

• s orbital will hold 2 electrons
• p orbital will hold 6 electrons
• d orbital will hold 10 electrons

Question 22

electron configuration of sodium

Answer 22

1s2 2s2 2p6 3s1

Question 23

electron configuration of calcium

Answer 23

1s2 2s2 2p6 3s2 3p6 4s2

Question 24

electron configuration of Sr2+

Answer 24

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6

Question 25

electron configuration of Ca2+

Answer 25

1s2 2s2 2p6 3s2 3p6

Question 26

electron configuration of Cs2+

Answer 26

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p5

Question 27

Cr2+

Answer 27

1s2 2s2 2p6 3s2 3p6 4s2 3d2

Question 28

what is unusual about chromium

Answer 28

when electrons occupy chromium, instead of being 4s2 3d4, it will be 4s1 3d5 an electron will move from the 4s orbital to the 3d orbital because there is a special stability associated with half filled orbitals. atoms would rather have 2 half filled than 1 filled.

Question 29

what is unusual about copper

Answer 29

copper will be 4s1 3d10 rather than 4s2 3d9 due to the stability associated with filled orbitals

Question 30

what electrons are lost when atoms become ions

Answer 30

electrons from the 4s orbital

Question 31

ionisation energy

Answer 31

the energy required to remove one mole of electrons from one mole of atoms in their gaseous state

Question 32

the energy required to remove one mole of electrons from one mole of atoms in their gaseous state

Answer 32

ionisation energy

Question 33

ionisation energy and half filled/filled shells

Answer 33

there is a stability associated with filled and half filled orbitals. this means that it requires more energy to remove electrons

Question 34

nuclear charge and ionisation energy

Answer 34

an increase in protons across periods means there is a stronger attraction for electrons, so requires more energy to remove

Question 35

atomic size and ionisation energy

Answer 35

as the atomic size increases down groups, the further away electrons are less attracted to the nucleus so require less energy to remove electrons

Question 36

sheilding and ionisation energy

Answer 36

inner electrons shield outer electrons from the nuclear charge of the nucleus, making them easier to remove. increases down groups

Question 37

electron configuration of aluminium (13 electrons)

Answer 37

1s2 2s2 2p6 3s2 3p1